A team of experts in mechanics, materials science, and tissue engineering at Harvard has created an extremely stretchy and tough gel that has potential as a replacement for damaged cartilage in human joints.

The new material, a hydrogel, is a strong hybrid of two weak gels. Not only can it stretch to 21 times its original length, but it is also tough, self-healing, and biocompatible — attributes that open up new opportunities in medicine and tissue engineering.

Importantly, the new hydrogel is capable of maintaining its elasticity and toughness over multiple stretches. Provided the gel has time to relax between stretches, the ionic bonds between the alginate and the calcium can “re-zip.” The researchers have shown that raising the ambient temperature can accelerate this process.


Also: Learn about polyurea-based aerogel monoliths and composites.